Background of the Invention
The invention and its various embodiments relate to methods for treating liquid streams containing quaternary ammonium compounds. In particular, the invention and its various embodiments relate to the addition of certain chemicals to a liquid stream containing quaternary ammonium compounds to reduce, eliminate, or sequester the quaternary ammonium compound in the liquid stream.
Description of Related Art
Quaternary ammonium compounds (QACs) are well known for their sanitization and disinfectant properties and are used, for example, in the medical and food industries for cleaning surfaces and equipment. Quaternary ammonium compounds are also added to a variety of industrial or process slurries and liquid streams to reduce and or eliminate biological activity that comes in contact with the treated streams. In some cases, quaternary ammonium compounds are add to certain process streams that may contaminant process equipment with biological activity, such as algae growth, as part of a cleaning-in-place process to sanitize and disinfect that process equipment. For example, quaternary ammonium compounds are added to process streams to minimize or eradicate zebra clam formation in process lines and equipment or to minimize biological activity, such as algae growth, in firefighting equipment that is used to move large volumes of water that may contain biological activity. Quaternary ammonium compounds are also used in oil and gas hydraulic fracking processes to minimize biological film build-up in the fractures in the ground.
However, such quaternary ammonium compounds are toxic, and discharge to the environment may have detrimental effects on surrounding biological activity. For example, discharge of a liquid stream that has been treated with a quaternary ammonium compound could be toxic to aquatic organisms existing in surrounding water systems and may pose a danger to human health as well. Accordingly, it would be desirable to treat such liquid streams to which quaternary ammonium compounds have been added to reduce, remove, or sequester such compounds, for example, prior to discharge of the liquid stream to the environment.
More particularly, QACs are used in the meat and meat byproduct industry in several different capacities. Most industrial meat plants have microbiologically mediated wastewater treatment plants. These plants are designed to maintain methanogenic conditions to create a co-gen fuel and precipitate chemically reduce or otherwise fix nitrogen and sulfur compounds thereby preventing the production of noxious vapors. It is thought by some plant operators that QACs are responsible for low methane production and malodors in their wastewater ponds.
In addition, many industries use QACs that are environmentally persistent and ultimately end up contaminating surface waters and potentially killing beneficial aquatic microorganisms. QACs are used in the medical industry for killing bacteria and viruses; however, their use is thought to contribute to the creation of superbugs. In addition, medical and other commercial uses of QAC cleaning solutions can be discharged to surface waters via storm drains and via municipal process water and water treatment plants. QACs are also used as an agricultural plant growth inhibitor, herbicide, pesticide and fungicide. These chemicals can be mobilized by rainfall runoff and contaminate surface waters.
QACs are also used in the manufacture of pharmaceutical products, as active ingredients in drugs, vaccines and as a way to extract polysaccharide capsules from microorganisms to develop drugs and vaccines.
Given the proven benefits and potential serious problems associated with every use of QACs, there is a need for new inventions that can control and enhance the behavior of QACs such that the environmental and public health risks can be mitigated, remediated or eliminated. In addition, new inventions can also enhance the efficacy and reduce dangerous side effects associated with QAC containing and/or derived drugs and vaccines. In addition, new inventions relating to agricultural uses of QACs are needed to reduce human health and environmental risks while increasing their effectiveness and scope of potential uses.